Simple Lit with Specular Highlights vs Lit Shader

I've been using the URP Lit shader for most of my materials but have been looking into the Simple Lit shader as a possible alternative. The Simple Lit material seems to have Specular Highlights disabled by default (at least they were every time I selected it); however, I can enable them and, with some texture tweaking, get back to (roughly) what I had with the Lit shader.

So my question is, is the Simple Lit shader with specular highlights turned on still more performant than the Lit shader since it, "does not calculate for physical correctness and energy conservation"?

 

Why does nobody answer this? It's a legit question and i want to know too

 

bump - also interested to know the answer to this!

 

Why not profile it with a demo or the game on the target device ?
I would also like to know

 

Why not read the documentation?

 

Please give us a link to that part of the documentation
/S

 

The Documentation does not answer this question. Furthermore, snarky comments like this serves no one.

 

That why i replied by sarcasm

 

In my tests on mobile, highend-ish xiaomi mi mix 2, simple lit with specuar lighlights is about twice as fast or less. This was on the build in render pipeline, but urp shader code is quite similar.

If you are targeting PC, most likely it doesn't matter and you won't see any differences. Or differences that matter.

 

Mi Mix 2 is quite old now can't be really considered as a High End-ish device anymore but that is really a good news we should expect better performance using Simple Lit

 

I can't comment on mobile, but I ran several tests on laptop and didn't notice any difference at all.

 

As already mentioned doing a test is surely the best way to figure this out for your specific case.

However. Even if it might be difficult to measure on desktop hardware there is two things to say about in which ways the simple lit shader is absolutely more performant than the regular lit shader.

The amount of code / instructions that goes into the lit shader is a lot higher, it is more complex, it does more stuff in a more pbr style (only regular lit uses the metallic workflow by default, but supports both). That means if you are looking for a lower instruction count, simple lit will be better.
With less complicated code it is easier to maintain if you plan to modify it (which you might not be doing but still a valid argument imo)

Especially in non-pbr, stylized scenarios the simple lit shader might actually be easier to work with.

 

A lot of non-answers here.
I built a game for the Oculus Quest 2 (Rogue Stargun; https://roguestargun.com)
I can tell you flat out, Simple Lit is vastly, vastly faster, particularly for things like landscapes.